The present invention relates to the field of cardiac surgery instrumentation and more specifically to the surgical method and apparatus optimized for coronary bypass operations.
Direct coronary artery revascularization on a beating heart was conducted, both experimentally and clinically, in the 1950""s and the 1960""s, without stabilization.
Challenges associated with this surgical technique are as follows:
complete anastomosis is very difficult to achieve due to the motion of the beating heart;
the technique is limited to vessels of a minimum diameterxe2x80x94again due to difficulty in the anastomosis technique on a beating heart;
lifting of the heart for revascularization of posterior arteries results in a precipitous drop in arterial pressure;
the learning curve for surgeons performing this technique is very high; negotiating the learning curve may represent significant surgical morbidity and mortality.
The development of the cardio-pulmonary machine for extracorporeal circulation (ECC) enables coronary operations on an arrested heart. This allows the surgeon to operate on a perfectly still heart and to manipulate the heart to expose the target artery.
At the present time, the standard coronary artery bypass graft (CABG) procedure typically requires a full median sternotomy and extracorporeal circulation through a cardio-pulmonary machine.
Even with the constant technological improvements achieved during the last twenty-five years, the advantages offered with ECC have been offset by morbidity and mortality related to the ECC itself. The inflammatory response, as well as systemic. microembolisms generated by ECC, induce to some extent a dysfunctional state of the brain, lungs and kidneys, which tends to increase with the aging of the patient. Furthermore, evidence suggests that when ECC can be avoided, the left ventricular function is better preserved, thereby reducing risk of post-operative complications.
As a result, alternate CABG procedures that do not rely on the use of ECC offer distinct advantages.
Recently, minimally invasive surgery, involving a partial sternotomy or mini-thorocotomy, has generated much interest since it removes precisely the need for ECC. This surgery does, however, have its limitations. It is adequate for only one or two coronary bypass grafts. Moreover, it does not provide access to the posterior descending or circumflex arteries, and impairs both the anastomosis and the surgeon""s vision due to the limited heart exposure.
These limitations may lead to future, more-invasive surgical interventions through partial or full sternotomy, if xe2x80x9cblockagesxe2x80x9d progress in those arteries which were not accessible via minimally invasive procedures.
Therefore, partial revascularization may lead to re-intervention which not only represents a disadvantage to the patient but a financial burden to the health care system.
It is therefore an object of the present invention to provide a surgical apparatus allowing to perform coronary surgery, in particular coronary artery revascularization, without the need for extra-corporeal circulation.
It is a further object of the invention to provide a surgical apparatus to perform complete revascularization of coronary arteries without the need for extra-corporeal circulation.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, on a beating heart.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, enabling grafting on all arteries of the heart and their respective branches, most particularly the right coronary (RC), the posterior descending artery (PDA), the left anterior descending artery (LAD) and diagonals, the branches of the circumflex artery (Cx) namely the obtuse marginal (1 through 4) and the postero-lateral branches.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, provided with positioning means being capable of being mounted in a plurality of locations on a sternum retractor or any other adequate support.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, simplifying the grafting process.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, with reduced costs associated with shorter time of surgery, reduced costs of surgical equipment, reduced surgical staff, significantly reduced risk of medical complications, and shorter hospital recovery stay.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, that is easy to utilize for surgeons and representing an evolution of current proven practice without the need for long retraining period.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, enabling surgeons to operate on all patients, especially those not well suited to minimally invasive techniques or well suited to conventional coronary artery bypass grafting (CABG) with extra corporeal circulation (ECC).
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, with a risk reduced procedure for the patient, a cost effective solution to reducing health care expenses, and an ergonomic layout enhancing the efficiency of surgeons.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, that is ergonomic, easy to deploy, easy to sterilize, and time efficient with respect to the multitude of attachments which might be needed during the course of open chest surgery.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, which optimizes accessibility to all different arteries requiring grafting irrespective of variations in personal physiology from one patient to another.
It is a further object of the invention to provide a surgical apparatus for performing coronary surgery, in particular coronary artery revascularization, that can be used with known types retractors, as a retrofit arrangement.
Another object of the invention is to provide positioning means for a surgical apparatus, in particular a heart stabilizer for performing coronary surgery, particularly coronary artery revascularization, without the need for extra-corporeal circulation.
Another object of the invention is to provide contacting means for a surgical apparatus, in particular a heart stabilizer for performing coronary surgery, particularly coronary artery revascularization, without the need for extra-corporeal circulation.
Another object of the invention is to provide a sternum retractor for performing coronary surgery, particularly coronary artery revascularization, without the need for extra-corporeal circulation.
As embodied and broadly described herein, the invention provides a surgical apparatus for coronary surgery on a patient comprising contacting means being capable of providing a mechanical force against at least a portion of the patient""s coronary organs according to its positioning with regard to said organs, positioning means to set said contacting means in a given substantially stable spatial position and orientation within a given volume, said contacting means being pivotingly connected to a sternum retractor via said positioning means.
This surgical apparatus enables performing coronary surgery, particularly coronary artery revascularization, without the need for extra-corporeal circulation. That is to say, the operation can be realized on a beating heart There is no need to use a cardio-pulmonary machine, which considerably reduces the costs of the operation. Without extra-corporeal circulation, mortality and morbidity rates are also reduced.
The surgery and graft process can be performed by only one surgeon and one assistant, as opposed to standard coronary artery bypass graft surgery which usually requires two surgeons and a perfusionist for ECC.
As embodied and broadly described herein, the invention also provides positioning means for a heart stabilizer for use in coronary surgery, said heart stabilizer comprising contacting means intended to provide a mechanical force against at least a portion of the patient""s coronary organs according to its positioning with regard to said organs, said positioning means being intended to set contacting means in a given substantially stable spatial position and orientation within a given volume and being connectable in at least one location to a sternum retractor, said contacting means being connectable to a movable free portion of said positioning means.
The contacting means can therefore be positioned in an almost unlimited number of positions and orientations to facilitate the intervention on any artery. This also brings high flexibility, as any patient, whatever the morphology may be, can be treated. Moreover, the adaptability of the apparatus facilitates the grafting process. For example, the right coronary artery is most accessible when the positioning means are mounted on the rack bar. The left anterior descending artery and diagonal arteries are most accessible when positioning means are mounted in the ending portion of the spreader arms. Access to the circumflex artery and posterior descending artery is enhanced when positioning means are mounted on the right side of the retractor, patient""s view.
Preferably, the positioning means comprise a sliding member providing relative movement between said sternum retractor and said positioning means. This provides great flexibility and facilitates the surgical manipulations.
As embodied and broadly described herein, the invention also provides positioning means for a heart stabilizer for use in coronary surgery, said heart stabilizer comprising contacting means intended to provide a mechanical force against at least a portion of the patient""s coronary organ according to its positioning with regard to said organs, said positioning means being intended to set contacting means in a given substantially stable spatial position and orientation within a given volume and being connectable in at least one location to a sternum retractor, wherein said positioning means comprise an articulation member for providing displacement of a member connected thereof with at least one degree of freedom, a positioning rod connectable to said articulation member, said contacting means being connectable to said positioning rod.
More specifically, under this preferred embodiment, the positioning means comprise a second articulation member for providing displacement of a member connected thereof, with at least one degree of freedom, said positioning rod being connectable to said second articulation member. The articulation member can advantageously be made of a resilient material.
In a specific example, the articulation member comprises at least one partly spherical member pivotingly maintaining a positioning rod member between two hollow cylindrical bodies. In another specific example, the articulation member comprises at least one partly spherical member pivotingly maintaining positioning rod member between two clamping members.
In another specific example, the xe2x80x9cquick-assemblyxe2x80x9d parts allow the positioning means to be placed in at (east six different orientations with respect to the sternum retractor, and consequently the patients heart: four orientations along the perimeter of the retracted chest cavity, and two cross-corner diagonal orientations. This maximizes the options for optimum accessibility to the target artery. It also provides the surgeon with flexibility during delicate surgical tasks like suturing, as he has access to strategic sections of the chest cavity that are free from all devices.
As embodied and broadly described herein, the invention also provides positioning means for a heart stabilizer for use in coronary surgery, said heart stabilizer comprising contacting means intended to provide a mechanical force against at least a portion of the patient""s coronary organs according to its positioning with regard to said organs, said positioning means being intended to set contacting means in a given substantially stable spatial position and orientation within a given volume and being connectable in at least one location to a sternum retractor, wherein said positioning means further comprise an articulation member for providing displacement of a member connected thereof with at least one degree of freedom, a positioning rod connectable to said articulation member, a second articulation member for providing displacement of a second member connected thereof with at least one degree of freedom, a second positioning rod connectable to said second articulation member, said contacting means being connectable to said second positioning rod.
As embodied and broadly described herein, the invention also provides contacting means being capable of providing a mechanical force against at least a portion of the patient""s coronary organs according to its positioning with regard to said organs within a given volume and comprising two substantially elongated contacting arms defining therebetween an arterial window.
As embodied and broadly described herein, the invention also provides a sternum retractor for use in coronary artery surgery, comprising: a rack bar extending transversally between the ending portions of a fixed spreader arm and a movable spreader arm, these arms both extending longitudinally in a direction substantially normal with regard to the rack bar, said movable arm being capable of being displaced along the rack bar and said spreader arms being provided with blades, contacting means intended to provide a mechanical force against at least a portion of the patient""s coronary organs according to its positioning with regard to said organs, positioning means intended to set contacting means in a given substantially stable spatial position and orientation within a given volume and being connectable in at least one location to a sternum retractor, said contacting means being connectable to a movable free portion of said positioning means.
All interfaces are intended and designed to keep the open chest cavity as ergonomic and accessible as possible, free from all peripheral tubing and connectors. All interfaces, design features and components are easy to sterilize.
The surgical equipment described herein can be used to perform multiple revascularizations on any of the coronary arteries or branches without repositioning the sternum retractor after initial deployment. The interfaces between the positioning means and the retractor are preferably designed to permit retractor spreader arm readjustment without disconnecting the positioning means setup. It can be used to perform multiple revascularizations by surgeons experienced in standard on-pump CABG with minimal training. It also can be used to perform revascularizations for both initial surgeries and reoperative cases.
The surgical equipment described herein provides the surgeon with visibility equal to that of standard CABG. Furthermore, in cases where unforeseen complications develop during surgery, the method described herein is not disadvantaged with the delays and complications associated with conversion from a minimally invasive CABG technique to full open chest surgery in cases. It is also not required for the patient to be placed on single lung ventilation, as is the case in some minimally invasive techniques.
The surgical apparatus described herein reduces the costs associated with standard CABG in particular in the following specific areas:
a cardio-pulmonary machine is not required;
a perfusionist to operate the cardio-pulmonary machine is not required;
less highly trained surgical staff is required to perform the surgery (one surgeon and assistant, compared to two surgeons);
reduced hospital stay is required because ECC is not used;
reduction in frequency of complications and associated costs;
reduction in operating time due to ergonomic design features of apparatus.